The historic district extends from the former Main Street Bridge to Long Street and encompasses the public buildings on either side of the Scioto River. The 580 foot long low-head concrete arch Main Street Dam was constructed in 1918 in response to the catastrophic 1913 flood. The dam helped reshape the Downtown Columbus Scioto River basin into a reflecting pool for the monumental riverfront buildings of teh Civic Center, which were influenced by the City Beautiful movement of the 1890s and early 1900s. Nearly a century after its construction, however, the dam had contributed to an unhealthy environment for aquatic life and was removed in late 2013 as part of teh Scioto Greenways river restoration project.